M48Z35AV ST Microelectronics, M48Z35AV Datasheet - Page 3

• Manufacturer Part Number: M48Z35AV
• Description: 256 Kbit 32Kb x8 ZEROPOWER SRAM
• Manufacturer: ST Microelectronics

Table 3. Operating Modes
Note: 1. X = V
Figure 3. Block Diagram
The M48Z35AY/35AV is a non-volatile pin and
function equivalent to any JEDEC standard 32K x8
SRAM. It also easily fits into many ROM, EPROM,
and EEPROM sockets, providing the non-volatility
of PROMs without any requirement for special
write timing or limitations on the number of writes
that can be performed. The 28 pin 600mil DIP
CAPHAT™ houses the M48Z35AY/35AV silicon
with a long life lithium button cell in a single pack-
age.
Deselect
Write
Read
Read
Deselect
Deselect
Mode
2. See Table 7 for details.
LITHIUM
IH
CELL
or V
IL
V
; V
SO
SO
4.5V to 5.5V
3.0V to 3.6V
to V
= Battery Back-up Switchover Voltage.
V
PFD
V
or
CC
SO
(1)
(min)
VOLTAGE SENSE
SWITCHING
CIRCUITRY
(2)
AND
V CC
V
V
V
V
E
X
X
IH
IL
IL
IL
POWER
V PFD
V
V
G
X
X
X
X
IH
IL
The 28 pin 330mil SOIC provides sockets with
gold plated contacts at both ends for direct con-
nection to a separate SNAPHAT housing contain-
ing the battery. The unique design allows the
SNAPHAT battery package to be mounted on top
of the SOIC package after the completion of the
surface mount process. Insertion of the SNAPHAT
housing after reflow prevents potential battery
damage due to the high temperatures required for
device surface-mounting. The SNAPHAT housing
is keyed to prevent reverse insertion.
V
V
V
W
X
X
X
SRAM ARRAY
IH
IH
IL
32K x 8
V SS
DQ0-DQ7
High Z
High Z
High Z
High Z
D
D
OUT
IN
M48Z35AY, M48Z35AV
Battery Back-up Mode
CMOS Standby
Standby
Power
A0-A14
DQ0-DQ7
E
W
G
Active
Active
Active
AI01619B
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